Coal-mining machine



I (No Model.)

S. G. LEGHNER.

GOAL MINING MACHINE.

'No. 287,032. Patented Oct. 23, 1883.

UNITED STATES SAMUEL o. LECHNER,

COAL-MINING MACHINE.

PATENT OFFICE.

OF COLUMBUS, OHIO.

SPECIFICATION forming part of Letters Patent No. 287,032, dated Occoher23, 1883.

Application filed July 28, 1883.

ing to be a full, clear, and exact description thereof.

My invention relates to improvements in that class of coal-miningmachines described in an application for Letters Patent filed by V. A.Lechner on March 31, 1888. In such machine the cutters are secured to apair of endless chains, driven by sprocket-wheels mounted 011 anadvancing carriage and moving in parallel lines in the same horizontalplane down the center until they encounter the breast of coal or otherrock, and then turning at right angles in opposite directions and movingseparately upward along the face of the breast, so that they exert theirpower in opposite directions and the strain of one set of cutters isupon or against that of the other.

To enable others skilled in the art to make and use my invention, I willnow describe it by reference to the accompanying drawings, in whichFigure 1 is a plan view of my improvement. Fig. 2 is an edge view. Fig.3 is an enlarged view of the chains, some of the links being shown insection. Fig. 4 is an end view of the cutter-carrying frame. Fig. 5 isaperspective view of one pair of idle-wheels, illustrating the passageof the chains over the same.

Like letters of reference indicate like in each.

In my improvement the shafts which drive the oppositely-movingcutter-chains are arranged one behind the other, as at a b, Fig. 1.These shafts, which are vertical, are provided with sprocket-wheels a b,by which the out terchains c and d are driven. The sliding frame, uponwhich the cutter-chains are in ounted, is composed of the bridge 0, barsf f, and cross-bar g, andis provided with suitable guideflanges, f, onthe under side of the bars f, designed to move in guides or ways in thestationary frame of the machine, as will be readily understood by thoseskilled in the art. At the outer ends of the cross bar g are idlesprocket-wheels, (on one side marked h h and on the other h 715*.) Atthe middle of the crossparts (No model.)

bar is a pair of idle sprocket-wheels, 'i i, mounted on a shaft, i Onthe bars f, near the carriage e, are idle sprocket-wheels k k and H. Thechains 0 (l are composed of cutterlinks 0 (1, having holes 0 d forsecuring the shanks of the cutters c (F, and intermediate links or bars,0* cl, pivotally secured to the links 0' d by rivets 0 (l and formingholes or recesses c d for the teeth of the sprocketwheels' The twodriving-shafts a I) turn in opposite directions, driving the chains 0 (lsimilarly.

The operation is. as follows: The machine being placed with its forwardend against a breast of coal or other rock, the cutter-chains are drivenin opposite directions, as indicated by the arrows. The chain cmakes theupper and the chain (1 the lower half of the cut. The sprocket-wheels ii hold the cutters up to their work at the middle of the cross-bar g,and prevent them from canting, and the wheels h h h h and It" k guideand direct the chains in their movements. The strain on the cutters ofone chain is against that of the other, and as they move past and nearto each other upon the same plane and are subject to the same strains,the machine is evenly balanced, and not liable to lateral displacement,nor to make an uneven cut. The cut made by this machine is clean andperfect throughout, there being no central portion of the rock remaininguntouched by the cutters and requiring to be chiseled out. Furthermore,the cut is cleaned by the lower cutters, d, of all the cuttings whichfall in the kerf, they being pushed out by the progressive movement ofthe cutters as they fall in front of them. The outer ends of the bars fare sup ported and braced against the strain of the out ters by thecross-bar g.

I do not limit myself to the form of chains shown and described, butinclude other forms of chains capable of carrying cutters and of beingdriven by suitable wheels.

What I claim as my invention, and desire to secure by Letters Patent, is

1. In a chain-cutter mining-machine, the combination of twocutter-chains driven side by side in opposite directions, twodrivingwheels turning in opposite directions for moving the chains, aframe upon which the cutten. chains are mounted, and idle-wheels at theouter end of the frame for guiding, directing, and

bar extending in the line of the cut and pro- I 5 vided with loosesprocket-wheels at each end and sprocket-Wheels in the middle, with twocutter-chains capable of moving side by side in opposite directions oversaid Wheels and along the outer edge of said cross-bar, substan- 2otially as and for the purposes described.

In testimony whereof I have hereunto set my hand this 13th day of July,A. D. 1883.

SAMUEL CLARENCE LECIINER.

"Vitnesses:

J. J. AOI-IAUER, B. F. AOHAUER.

